Dat file format

Name	Data type	Description
itemsData	char[datFileSize - itemsListSize - 8]	Items binary data
itemsListCount	unsigned int	Number of items in the list
itemsList	itemsListEntry[itemsListCount]	List of items
itemsListSize	unsigned int	Size of items list in bytes(including itemsListCount)
datFileSize	unsigned int	Full size of DAT file

struct itemsListEntry {
    unsigned int filenameSize;   // filename size in bytes
    char filename[filenameSize];
    unsigned char compressed;    // 0 - uncompressed,  1 - compressed
    unsigned int unpackedSize;
    unsigned int packedSize;
    unsigned int dataOffset;     // offset from file beginning in bytes 
}

Items list reading sequence:

1. Go to (size of DAT file - 4 bytes)
2. Read datFileSize
3. Compare datFileSize and size of DAT file. If not equal then file is corrupted
4. Go to ( datFileSize - 8)
5. Read itemsListSize
6. Go to ( datFileSize - itemsListSize - 8)
7. Read itemsListCount
8. Read itemsListEntry
9. Repeat previous action itemsListCount times

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